The Molecular Biophysics Training Grant has nucleated the biophysics community on the UCSD campus in many ways. Its primary goal has been to provide a rigorous, dynamic, and strongly interdisciplinary training program for graduate students from the departments of Chemistry and Biochemistry, Physics, and Biology. Broad research opportunities are provided by 28 training faculty from these departments as well as Pharmacology, Cell and Molecular Medicine, and Bioengineering. Training faculty are housed on the main campus, the School of Medicine, the San Diego Supercomputer Center, and the Salk Institute. The new Structural Biology Program at the Salk Institute is an integral part of our program. Important goals of our program have been to nucleate the biophysical faculty and to provide the infrastructure, particularly in the form of instrumentation cores, that will enable our students to achieve their maximal potential. Over the past four years we have established a Molecular Biophysics Laboratory that includes state-of-the-art electron spin resonance, surface plasmon resonance, analytical ultracentrifugation, and circular dichroism. We have also established a mass spectrometry core with high resolution MALDI-TOF and nanospray quadrupolar-TOF instruments. These cores did not exist four years ago when this renewal began. In addition, the NMR and Crystallography cores have been expanded considerably. Trainees are supported for up to three years, beginning typically in the second year of graduate study. The training program achieves its goals by (1) Monthly meetings where students, postdoctoral fellows and faculty meet to hear students discuss their work. This has evolved into a highly interactive discussion, a catalyst for interactions, and a self-identified community of molecular biophysicists. (2) An annual retreat where all of our students either talk or present posters and new faculty are introduced. (3) Seminar speakers invited and hosted by trainees. (4) Sponsored travel for students to scientific meetings and workshops on various instrumentation, in some cases sponsored workshops here at UCSD. (5) Annual luncheon with the Steering Committee comprised of: S. Taylor, J.A. McCammon, P. Ghosh, J. Onuchic, and J. Schroeder. Under the joint leadership of Taylor and McCammon, we have built a highly interdisciplinary program that spurs experimental and theoretical molecular biophysics. Our goal over the next grant period is to continue to grow our program, to solidify our cores and to create new ones as the demands arise, and to expand the visibility of our program so that we attract the very best students. We shall continue to work with our departments and our administration to expand the presence of molecular biophysics on the UCSD campus during the expansion phase planned for the next decade. Based on plans for increased recruitment of faculty and new buildings, we are requesting support for 10 trainees.